机翼结构相似颤振模型制造的模态频率误差修正方法

Error-correction Method of the Modal Frequency for the Manufacturing of Wing Flutter Model with Structure-similarity

针对以几何和性能指标精确性为目标的复合材料结构相似颤振模型制造问题,基于复合材料层合板的弯扭耦合效应,提出一种在模型蒙皮内侧增加复合材料铺层,改变模型刚度分布,并辅以质量分布调整,从而实现颤振模型模态频率误差修正的方法。通过分析误差性质,结合具体制造工艺,将模态频率误差转化为刚度误差。以模型结构动力学有限元分析为基础,采用连续二次规划的优化策略,建立以模态频率误差反求新增铺层方式的误差修正方案的优化设计。对某大展弦比机翼的颤振模型主盒段进行数值分析,分别以弯曲频率误差和扭转频率误差的修正为例,证明该误差修正方法的有效性。同时该方法对以性能精确性为目标的高性能产品制造具有借鉴意义。

The flutter model must ensure the precision of the geometry and the performance target. According to the structure dynamics principles and the bending-twisting coupling effect of composite, here an error correction method of frequency is presented for the manufacturing issue of the composite structure-similarity flutter model（ComSFM）. The core of the method is to add appropriate composite laminates on the skin to change the stiffness distribution of the ComSFM, and then the error of frequency will be corrected by adjusting weight to change the mass distribution. In this method, the error of the modal frequency is converted into the error of the stiffness distribution by analyzing the property of the error and the manufacturing process of the model. The finite element model of the structural dynamics and the optimal strategy of the NLPQL are adopted to construct the optimum design for the error correction scheme. The specific way of the adding composite is achieved by using this design method. The wing box of the airliner is chosen as the numerical example, and errors of the bending frequency and torsional frequency about this model are corrected respectively. Results show that the error correction method is effective. And this method can also be beneficial to the manufacturing of the product that the target is the performance precision.